Malicious PDF — malware analysis report

Static analysis result for SHA-256 81d8d335b22bc872…

MALICIOUS

PDF

82.3 KB Created: 2021-08-31 06:14:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 1044ab0024018b65f6b446a55a4ddeae SHA-1: b32810ec356abf92dcb90c59f843806d8037db35 SHA-256: 81d8d335b22bc87291c19c2f795ced4cfbe6683057561a23185896f4b983e290
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of links pointing to various domains, many of which are hosted on compromised WordPress sites. The ClamAV detection and ML classifier strongly indicate malicious intent, specifically identified as phishing. While no scripts were explicitly extracted, the structure and URL patterns suggest a link farm designed to redirect users, likely as part of a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e8363fca218---95922621801.pdf In PDF document text
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088716157d8a---lomefowiwogesikutepopu.pdfIn PDF document text
    • https://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/160f4ed7f19c61---50521437901.pdfIn PDF document text
    • https://www.conkite.com/wp-content/plugins/super-forms/uploads/php/files/0c38d7db29951e67201342bb92af591e/60719356432.pdfIn PDF document text
    • https://saftanton.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1608848bce4996---90884939445.pdfIn PDF document text
    • https://www.msolartop.cz/wp-content/plugins/formcraft/file-upload/server/content/files/1608d862e7341c---76132543062.pdfIn PDF document text
    • http://plenar.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160722e2a4541e---68181107641.pdfIn PDF document text
    • https://bcm.es/files/galeria/files/64914388795.pdfIn PDF document text
    • http://iideree.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609f7cfe6aff6---gutezag.pdfIn PDF document text
    • http://ecohouse-lab.com/userfiles/file/lafututujidotoduderakijap.pdfIn PDF document text
    • https://playgametoday.ru/wp-content/plugins/super-forms/uploads/php/files/1924554c7485fb8c97e82f19046f1993/vufiramepufodabonuz.pdfIn PDF document text
    • http://avvocato-callegaro.it/public/file/zibomewamuwonevot.pdfIn PDF document text
    • https://marciasmithconsulting.com/wp-content/plugins/super-forms/uploads/php/files/98a177f1c151811dc8405d3f122e8dac/vuwobixo.pdfIn PDF document text
    • http://findacommodity.com/upload/file/90773460750.pdfIn PDF document text
    • https://duvarkagidierzincan.com/userfiles/file/81705189214.pdfIn PDF document text
    • http://montrealinkwell.com/clients/c/c4/c478fb9048b4d856ed1aa16e2301f982/File/semove.pdfIn PDF document text
    • http://artepcb.com/upload/files/dawonagijoseniwirixobo.pdfIn PDF document text
    • https://africanresearchcenter.com/userfiles/file/2560407254.pdfIn PDF document text
    • http://ztkammer.at/uploads/file/8880548820.pdfIn PDF document text
    • https://assurancemauricie.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f85d6c8833---28086660372.pdfIn PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/1lbmevt1lllmlsp4pbu7tuleq7/kokugazefexuvewuma.pdfIn PDF document text
    • https://soba05.org/wp-content/plugins/super-forms/uploads/php/files/bdc2aff8d5d207466032c834132afc36/pumugelujalo.pdfIn PDF document text
    • http://bdn10.cz/files/file/sixajuleneba.pdfIn PDF document text
    • http://auto-spec.ca/fck/file/80105344504.pdfIn PDF document text
    • https://www.stamfordtaxis.com/wp-content/plugins/super-forms/uploads/php/files/6s2rp4h662m2rvdbnn3fpmv6vp/rixepoxixedenowufo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=how+is+weight+a+vector+quantityPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dd6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD6C 16992 bytes
SHA-256: d00c704d7fc88a340e4eb8f5ed71f4fb1775ae6292766fe86fa8c05c52b57cf4
font_01_sfnt_off00010971.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10971 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012188.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12188 10964 bytes
SHA-256: d3300d8d90deae183ce1eed702bb853fb535b010167f9cbcdb8a72ad82a9e7f9